Concorde Career College, Portland
ST120 Unit 2:The Heart
The HeartObjectives:
Evaluate the anatomic development of the heart
Describe the basic anatomy of the heart, including coverings, wall, chambers, and valves
Trace the flow of blood into, through, and out of the heart
Evaluate myocardial infarctionDescribe the conduction system of the heartDescribe basic cardiac dysrhythmias and
electrocardiogram elements
The Heart: Part of the Cardiovascular System
Cardiovascular (Circulatory)
SystemBloodHeartArteriesVeinsCapillaries
Cardiovascular System
Cardiovascular
Pertaining to the heart and blood
vessels.
Heart Heart the pump
Peripheral vascular system Peripheral vascular system arteries – carry blood AWAY from the heartVeins – carry blood TOWARD the heartcapillaries – tiny webs that connect the arteries
and veins peripherally; gas exchange takes place called internal respirations
The lymphatic system also part of the circulatory system
Cardiovascular System
Function of the Blood Circulatory System-- Simply→ Transportation
Blood TransportsHormonesEnzymesOxygenCarbon dioxide
Carries nutrients (from various organs) and oxygen (from the lungs) to the body’s cells for use, which creates waste
The waste (includes carbon dioxide) is carried from the cells to the excretory organs. Example-Lungs expires carbon dioxide
Cardiovascular System
The Heart
Cardiovascular SystemGeneral Information
Located in the mediastinum
Slightly bigger than a fist
Contracts approximately 72 times per minute
2/3 of the heart is located toward the left of the thoracic cavity
Cardiovascular SystemFunction of the Heart
PumpSystole (contraction)Diastole (relaxation)
Coverings of the HeartPericardium – loose fitting sac that covers
the entire heartSerous pericardium – inside the
pericardium; composed of two layersParietal layer- lines the inside of the
pericardiumVisceral layer- thin layer that covers the
heartPericardial cavity – space located between
the Parietal layer and the Visceral layer; contains pericardial fluid to reduce friction
Pericardium
Heart AnatomyEpicardium is the outer layer of the heart wallEach chamber is lined by a thin layer of tissue called the
endocardiumThe wall of each chamber is composed of cardiac
muscle tissue called the myocardium
Cardiovascular System
Chambers of the Heart
Atria (receiving chambers)
Ventricles (pumping chambers)
Separated into right and left sides by the septum
HEART CHAMBERS
UPPER CHAMBERS – RIGHT AND LEFT ATRIA which receives oxygen poor blood returning from lungs and body
LOWER CHAMBERS – RIGHT AND LEFT VENTICLES moves oxygen rich blood into arteries
1414
Cardiovascular System
Heart Valves
Tricuspid (right atrioventricular)
Bicuspid (mitral or left atrioventricular)
Pulmonary (semilunar)
Aortic (semilunar)
HEART VALVES
why do we need heart valves? To keep the blood flowing one direction
The valve that separates the right atrium from the right ventricle is called the?
TRICUSPID VALVE
The valve that separates the left atrium from the left ventricle is called the?
BICUSPID VALVE or MITRAL
16
Heart ValvesSL or semilunar valves located between the two ventricles
and the arteries that carry the blood away from the heart
17
Heart ValvesPulmonary semilunar valve is located at the beginning of the
pulmonary artery that allows blood to flow from the right ventricle to the lungs
Aortic semilunar valve is located at the beginning of the aorta and allows blood to flow out of the left ventricle into the aorta
18
Cardiovascular System
Chordae Tendineae
Stabilize valve flaps to promote one way blood flow
Cardiovascular System
Myocardial Blood Supply
Right coronary arteryLeft coronary arteryCircumflex arteryRight marginal branchAnterior and posterior
interventricular arteries
Coronary arteries and Coronary veins
.
Blood Flow through the HeartThe right side of the heart receives oxygen-poor
blood from the veins•Blood enters right atrium through the superior vena cava and the inferior vena cava
22
Blood Flow through the HeartWhen the heart “beats”, first the atria contract
simultaneously (atrial systole)
23
Blood Flow through the HeartThen the ventricles fill with blood and they contract togetherWhen the ventricles contract, blood in the right ventricle is
pumped through the pulmonary semilunar valve into the pulmonary artery and to the lungs, where it is oxygenated
24
Blood Flow Through the HeartOxygenated blood returns to the left atrium through 4
pulmonary veinsIt then passes through the left AV or bicuspid valve to the
left ventricle
25
Blood Flow Through the HeartFrom the left ventricle, the blood is pumped out
through the aortic semilunar valve to the aortaFrom the aorta to the rest of the body!
26
Conduction System
Electrical impulses that signal the heart to beat
All cardiac muscle fibers in each region of the heart are electrically linked together!
Intercalated disks are electrical connectors that join the muscle fibers
27
Cardiovascular System
Conduction SystemSinoatrial (SA)
nodeAtrioventricular
(AV) nodeBundle of HisRight and left
bundle branchesPurkinje fibers
29
Cardiac Cycle
Each complete heartbeat is called a cardiac cycle
Consists of alternating systole (contraction) and diastole (relaxation) of atria and ventricles
Stroke volume is the volume of blood ejected from the ventricles during each beat
Cardiac output is the volume of blood ejected from the left ventricle into the aorta
30
PathologyCoronary Atherosclerotic Heart Disease - a condition
in which fatty material collects along the walls of arteries. This fatty material thickens, hardens (forms calcium deposits), and may eventually block the arteries; endothelial cell dysfunction
Myocardial Ischemia - (reduced blood supply) of the
heart muscle, usually due to the blockage caused by Coronary Atherosclerosis
Angina pectoris – chest pain due to Myocardial Ischemia
Myocardial Infarction (MI) – death of heart muscle tissue from Myocardial Ischemia, which leads to sudden cardiac death
PathologyVentricular fibrillation – major dysrhythmia of the
ventricles. They flutter without coordination which results in lack of blood pumped out of the heart
Heart block – a disease in the electrical system of the heart
Asystole – cardiac arrest
Myocardial rupture – blood escaping the ventricles and entering the pericardial sac; can result in cardiac tamponade
Cardiac aneurysm – ballooning of the ventricular wall resulting in increases pressure in the ventricles
Coronary Atherosclerotic Heart Disease
Coronary Atherosclerotic Heart Disease
Coronary Atherosclerotic Heart Disease
TreatmentsPreformed in the Cardiac Catheterization
lab (Cath Lab)
Percutaneous Transluminal Coronary Angioplasty (PTCA)
Coronary Stent
Intra-coronary Thrombolysis
Coronary Stent - A Treatment for Coronary Atherosclerotic Heart Disease
Percutaneous Transluminal Coronary Angioplasty (PTCA)
TreatmentsPreformed in the Heart Room in the OR
Suite Coronary Artery Bypass Grafting (CABG)
Permanent pacemaker
Surgical Treatment : Coronary Artery Bypass Grafting (CABG)
Possible Grafts for CABG1. Saphenous vein 2. Internal thoracic arteries (mammary)3. Radial Artery
Saphenous Vein Harvesting
Postoperative Healing
Endoscopic Saphenous Harvesting
Mammary Artery Harvesting
Internal Mammary Artery
Radial Artery Harvesting
Cardiopulmonary BypassIdentify the locations of the tube insertions into the circulatory system
Permanent Pacemaker
Dysrhythmias Sinus Dysrhythmia – most common;
related to vagal nerve impulses to the SA node; benign
Sinus Tachycardia – heart rate of 100 beats or more per minute
Sinus Bradycardia - heart rate of 60 beats or less per minute
Atria DysrhythmiasDysrhythmias originating in the atria:Premature atrial beat – often associated
with stress or consumption of caffeine or nicotine
Atrial tachycardia – atrial rate of 150-250 beats per minute; usually benign
Atrial flutter - atrial rate of 250-350 beats per minute; can result in increased ventricular rate and decrease in oxygen
Atrial fibrillation - atrial rate of 350-600 beats per minute; results in increased ventricular rate and decrease in oxygen
Ventricular DysrhythmiasBenign PVC’s – less than 5 per hour;
absence of heart diseaseComplex PVC’s – greater than 10-30 per
hour; with or without heart diseaseMalignant PVC’s – same as complex except
with left ventricular dysfunction Ventricular tachycardia – 140-250 beats per
minuteVentricular flutter – regular contractions
but at a fast rate of 250-350 per minute
ElectrocardiogramECG or EKG
Electrical signals can be picked up form the body surface and transformed into visible tracings by an instrument called an electrocardiograph
The electrocardiogram is the graphic record of the heart’s electrical activity
ECG3 characteristic deflections or waves
P wave – depolarization (triggers contraction) of atria
QRS complex - depolarization (triggers contraction) of ventricles
T wave - repolarization of ventricles
Cardiothoracic ProceduresFeatures of the ECG Paper
ECG Electrical Correlation
Electrocardiograph(Normal Sinus Rhythm)
Sinus Rhythm
Occasional (Incidental) PVC
Bigeminy(PVC Every Other Beat)
Ventricular Fibrillation(V Fib)
Premature Atrial Contraction(PAC)
Atrial Fibrillation
Asystole